> What stops him from taking your MVP project and doing it with someone else?

Nothing whatsoever. But then again, since we're talking about ideas that would be on the shelf anyway not a whole lot would be lost.

And the OP would be outed and burned beyond recovery. Anybody stupid enough to risk that on a forum as widely recognized as this one would be seriously out of their mind.

> What stops him from telling others about your project so they can copy it or do it better?

Again, absolutely nothing. What stops YC from doing something like that when you apply to YC?

This all boils down to basic trust, and at some point in the business game you're going to have to extend yourself far enough that you can get burned a little if you want to up your game.

This guy is extending himself far enough that he'll get burned a lot if he abuses the trust he's getting here. That alone should count as some insurance.

Imagine how many upvotes a post along the lines of "That hmexx dude is XXX YYY in real life and screwed me over" will get. Probably even more than "That hmexx dude is XXX YYY in real life, we did this thing and have just picked up follow on investment".